1. Field
Embodiments of the present disclosure relate to an air conditioner having a control unit cooling portion which cools a control unit to control a compressor using a refrigerant.
2. Description of the Related Art
In a conventional refrigeration device, a control unit cooling portion which cools a control unit to control a compressor using a refrigerant is installed to a main refrigerant circuit configuring a series of refrigeration cycles. Therefore, there is a problem in that, at low differential pressure when the refrigeration cycles are activated, a flow rate of a refrigerant to cool the control unit is not secured in the control unit cooling portion and thus the control unit is excessively heated.
In addition, in a conventional structure of providing the control unit cooling portion in the main refrigerant circuit, there is a problem in that the control unit is insufficiently cooled when a flow rate of the refrigerant within the main refrigerant circuit needs to be reduced due to oil foaming or the like in which lubricant is brought to an indoor unit in quantity. Thus, it is undesirable to install the control unit cooling portion to the main refrigerant circuit configuring a series of refrigeration cycles so as to cool the control unit.
Meanwhile, as the related art intended to improve efficiency of the refrigeration cycles, aside from the main refrigerant circuit, a refrigeration device is already known in which an injection circuit diverging from the main refrigerant circuit is formed. For example, see Japanese Patent Publication No. 2010-2112. In the refrigeration device disclosed in Japanese Patent Publication No. 2010-2112, an inverter cooling portion as the control unit cooling portion is provided within the injection circuit. Accordingly, a portion of a refrigerant diverging from the main refrigerant circuit is introduced through an expansion valve into the inverter cooling portion, and an inverter device, which is a type of the control unit, is cooled by the introduced refrigerant (see FIG. 1 in Japanese Patent Publication No. 2010-2112).
However, in the technique disclosed in Japanese Patent Publication No. 2010-2112, since the inverter device, which is a type of control unit, is insufficiently cooled, desired cooling efficiency may not be obtained. This is because the refrigerant introduced into the inverter cooling portion may not be maintained to a state suitable for cooling in the configuration of the refrigeration device in Japanese Patent Publication No. 2010-2112.